JP2010243545A - Light modulation element positioning method for projector and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily perform light modulation element positioning with high accuracy so that the respective image light beams emitted from two light modulation element units are in the desired pixel shifting state. <P>SOLUTION: In a first light modulation element unit 400, for the respective pixels of a light modulation element for a certain color light beam among first to third color lights, positioning is performed so that the respective pixels of two light modulation elements for the two other color lights are put in a predetermined pixel shifting state. In a second light modulation element unit 600, for the respective pixels of the two light modulation elements for the two color lights, positioning is performed so that the respective pixels of the light modulation element for the one color light are put in a predetermined pixel shifting state. The color light from a specified light modulation element of the first light modulation element unit is emitted as a first image light, the color light from a specified light modulation element of the second light modulation element unit is emitted as a second image light, and the first light modulation element unit and the second light modulation element unit are positioned so that the combined light is a predetermined color. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light modulation element position adjusting method for a projector and a projector.

  A projection method is known in which the positions of the two projectors are adjusted so that the corresponding pixels of the light modulation elements of the two projectors coincide with each other, and the same image is projected from the projectors onto the same screen (hereinafter referred to as “projection method”). Then, it is called “stack projection”). The brightness of the image light projected by such stack projection is almost doubled, and the image light projected on the screen is very bright. In addition, in order to obtain a higher resolution image, the same image may be projected from each projector in a state where the corresponding pixels of the light modulation elements of the two projectors are shifted by ½ pixel in the oblique direction. Is performed (called projection by pixel shifting).

  However, in order to perform the stack projection and the pixel shift projection as described above, it is necessary to adjust the positions of the two projectors with high accuracy, and generally it is not possible to make an appropriate adjustment unless you are an expert. . In particular, in the case of performing pixel shift projection, it is difficult to adjust the position reference and target when setting the desired pixel shift state.

  On the other hand, a projector having two light modulation element units (referred to as a first light modulation element unit and a second light modulation element unit) in one projector is known (for example, see Patent Document 1). The projector disclosed in Patent Document 1 gives light of a first polarization component (referred to as a P-polarization component) emitted from a light source to the first light modulation element unit and a second polarization component (S) emitted from the light source. By providing the second light modulation element unit with light having a polarization component), the first image light is emitted from the first light modulation element unit, and the second image light is emitted from the second light modulation element unit. It has become so. The first image light and the second image light are combined by a polarization combining optical system and projected onto a screen by a single projection optical system. In the first light modulation element unit and the second light modulation element unit, the RGB light modulation elements and the synthesis optical system for synthesizing the RGB color lights output from the RGB light modulation elements are integrated. Suppose that it has a structure.

  According to the projector disclosed in Patent Document 1, since there are two light modulation element units (a first light modulation element unit and a second light modulation element unit) in one projector, the first light modulation element unit In the second light modulation element unit, each of the RGB light modulation elements (liquid crystal panels) is adjusted with high precision so that the corresponding pixels of the respective RGB light modulation elements (liquid crystal panels) match. If the positions of the first light modulation element unit and the second light modulation element unit are adjusted with high precision so that the corresponding pixels coincide with each other, the first light modulation element unit The first image light output from the second image light and the second image light output from the second light modulation element unit are displayed in a desired pixel shift state. Also it is considered to be possible to.

Japanese Patent Laid-Open No. 10-304284

  However, in the projector disclosed in Patent Document 1, the first image light output from the first light modulation element unit and the second image light output from the second light modulation element unit on the screen, for example, When trying to set a pixel shift state that is shifted by 1/2 pixel in the oblique direction, it is necessary to adjust the positions of the first light modulation element unit and the second light modulation element unit with high accuracy when the projector is assembled. is there. As described above, when performing pixel-shifted projection, it is difficult to adjust the position reference and target when setting the desired pixel-shift state. There is a problem of getting worse.

  Therefore, the present invention can easily and accurately adjust the position of the light modulation element for setting each image light emitted by the two light modulation element units to a desired pixel shift state. It is an object of the present invention to provide a position adjusting method for a light modulation element of a projector and a projector.

  (1) The light modulation element position adjusting method of the projector according to the present invention includes three light modulation elements corresponding to the first color light, the second color light, and the third color light having the first polarization component, and the three light modulation elements, respectively. A first light modulation element unit including a first combining optical system that combines the modulated color lights and emits a first image light; a first color light having a second polarization component; a second color light; and a third color light. A second light modulation element unit comprising three light modulation elements corresponding to color light and a second combining optical system for combining the respective color lights modulated by the three light modulation elements and emitting a second image light And a polarization combining optical system that combines the first image light emitted from the first light modulation element unit and the second image light emitted from the second light modulation element unit to emit combined light. Projector A modulation element position adjusting method, wherein one color light of the first color light, the second color light, and the third color light is set as a first group, and the other two color lights are set as a second group, and the first light modulation is performed. Among the three light modulation elements in the element unit, corresponding pixels of two light modulation elements corresponding to the color light of the second group are matched, and one corresponding to one color light of the first group First light that adjusts the position of each pixel of the light modulation element such that each pixel of the two light modulation elements corresponding to the two color lights of the second group is shifted by a predetermined amount in a predetermined direction. Two color lights that are the second group in the modulation element position adjustment step and the first light modulation element position adjustment step are set as a third group, and the first group is set as the first group in the first light modulation element position adjustment step. And the corresponding pixels of the two light modulation elements corresponding to the two color lights of the third group of the three light modulation elements in the second light modulation element unit match each other. In addition, for each pixel of the two light modulation elements corresponding to the two color lights of the third group, each pixel of the one light modulation element corresponding to the one color light of the fourth group is located in a predetermined direction. A second light modulation element position adjustment step for adjusting the position so that a fixed amount of deviation occurs, and a color light from a specific light modulation element among the three light modulation elements in the first light modulation element unit A step of emitting color light as a second image light from a specific light modulation element of the three light modulation elements of the second light modulation element unit, and emitting the first image light and the first image light. Adjusting the position of the first light modulation element unit and the second light modulation element unit so that the color of the combined light obtained by combining the two image lights by the polarization combining optical system becomes a predetermined color. And a position adjusting step.

As described above, the light modulation element position adjusting method of the projector according to the present invention divides the three color lights into two groups, and in the first light modulation element unit, one color light is assigned to the first group and the other two. One color light is set as the second group. On the other hand, in the second light modulation element unit, the two color lights that are the second group are the third group, and the one color light that is the first group is the fourth group. In each of the first light modulation element unit and the second light modulation element unit, the two light modulation elements corresponding to the two color lights respectively correspond to the corresponding pixels, and the corresponding pixels correspond to a predetermined pixel. The position is adjusted so as to be in a state shifted by a predetermined amount in the direction (ideal pixel shift state).

  In this way, by adjusting the position in advance so that each light modulation element is in an ideal pixel shift state in each of the first light modulation element unit and the second light modulation element unit, By simply adjusting the positions of the light modulation element unit and the second light modulation element unit, the first image light emitted from the first light modulation element unit and the second image emitted from the second light modulation element unit are It is possible to display in an ideal pixel shift state. Further, when the positions of the first light modulation element unit and the second light modulation element unit are adjusted, the color of the combined light obtained by combining the first image light and the second image light with the polarization combining optical system becomes a predetermined color. As described above, since the position of the first light modulation element unit and the second light modulation element unit may be adjusted, the target for position adjustment is determined, so that the position adjustment can be performed easily and with high accuracy.

  (2) In the light modulation element position adjustment method of the projector according to the aspect of the invention, the first light modulation element position adjustment step and the second light modulation element position adjustment step include the first light modulation element unit and the second light. The modulation element unit is performed as a step before being incorporated into the projector, and the light modulation element unit position adjusting step is performed in a state where the first light modulation element unit and the second light modulation element unit are incorporated into the projector. It is preferable.

  As described above, the first light modulation element position adjustment step and the second light modulation element position adjustment step are performed in advance as steps before incorporating the first light modulation element unit and the second light modulation element unit into the projector. Thus, the assembly of the projector can be facilitated. The first light modulation element position adjustment step and the second light modulation element position adjustment step are performed using a dedicated position adjustment device. Such a dedicated light modulation element position adjusting device can use a high-performance optical system such as a projection lens as compared with a commercially available projector, and therefore can perform highly accurate position adjustment, and relatively Position adjustment can be easily performed.

  (3) In the light modulation element position adjusting method of the projector according to the aspect of the invention, the specific light modulation element may be one light modulation corresponding to one color light of the first group in the first light modulation element unit. Preferably, in the second light modulation element unit, there are two light modulation elements corresponding to the two color lights of the third group.

  As a result, the combined light that combines one color light emitted from the first light modulation element unit and the other two color lights emitted from the second light modulation element unit is emitted from the polarization combining optical system. Therefore, the degree of position adjustment can be appropriately determined based on the color of the combined light.

  (4) In the light modulation element position adjusting method of the projector according to the aspect of the invention, the specific light modulation element may be two light modulations corresponding to the two color lights of the second group in the first light modulation element unit. It is preferable that the second light modulation element unit is one light modulation element corresponding to one color light of the fourth group.

  In this case, the combined light combining the two color lights emitted from the first light modulation element unit and the other color light emitted from the second light modulation element unit is emitted from the polarization combining optical system. Therefore, the degree of position adjustment can be appropriately determined based on the color of the combined light.

(5) In the light modulation element position adjusting method of the projector according to the aspect of the invention, the predetermined direction when performing position adjustment so as to be shifted by a predetermined amount in the predetermined direction is an oblique direction, and the predetermined amount is A half pixel is preferable.

  As a result, the image displayed on the screen can be made an image having almost twice the resolution.

  (6) In the light modulation element position adjusting method of the projector according to the aspect of the invention, the first to third color lights may be red, green, and blue, and one of the first groups in the first light modulation element unit. One light modulation element corresponding to the color light is a light modulation element corresponding to the green light, and two light modulation elements corresponding to the two color lights of the second group are a light modulation element corresponding to the red light and Two light modulation elements corresponding to two color lights of the third group in the second light modulation element unit correspond to light modulation elements corresponding to red light and blue light. Preferably, one light modulation element corresponding to one color light of the fourth group is a light modulation element corresponding to the green light.

  Thus, when performing the light modulation element unit position adjustment step, the first light modulation element unit and the second light modulation element unit are positioned so that the combined light emitted from the polarization combining optical system is white (W). Since it is only necessary to adjust the position, the position adjustment target for the position adjustment of the first light modulation element unit and the second light modulation element unit becomes clear, and the position adjustment can be performed easily and with high accuracy. That is, when a light modulation element corresponding to one color light (green light) of the first group is driven in the first light modulation element unit, green light is emitted from the first light modulation element unit, When two light modulation elements corresponding to two color lights (red light and blue light) of the third group are driven in the light modulation element unit, red light and blue light are emitted from the second light modulation element unit. Therefore, the combined light emitted from the polarization combining optical system is white (W). In the first light modulation element unit, two light modulation elements corresponding to two color lights (red light and blue light) in the second group are driven, and one color light (in the fourth group in the second light modulation element unit ( The same applies to the case where one light modulation element corresponding to green light is driven.

  (7) The projector according to the invention includes three light modulation elements corresponding to the first color light, the second color light, and the third color light having the first polarization component, and the respective color lights modulated by the three light modulation elements. A first light modulation element unit including a first combining optical system that combines and emits first image light, and three lights corresponding to the first color light, the second color light, and the third color light having a second polarization component A second light modulation element unit comprising a modulation element and a second combining optical system for emitting the second image light by combining the respective color lights modulated by the three light modulation elements; and the first light modulation A projector comprising: a polarization combining optical system that combines first image light emitted from an element unit and second image light emitted from the second light modulation element unit and emits combined light; 1 light modulator The position of the three light modulation elements of the unit is adjusted by the first light modulation element position adjustment step in the light modulation element position adjustment method of the projector according to any one of claims 1 to 6, and The positions of the three light modulation elements of the light modulation element unit are adjusted by the second light modulation element position adjustment step in the light modulation element position adjustment method for a projector according to any one of claims 1 to 6, The position of the first light modulation element unit and the second light modulation element unit is adjusted by the light modulation element unit position adjustment step in the light modulation element position adjustment method for a projector according to any one of claims 1 to 6. It is characterized by being.

According to the projector of the present invention, it is possible to project an image in an ideal pixel shift state, and thus it is possible to display a high-resolution image. Further, since the position adjustment between the first light modulation element unit and the second light modulation element unit can be performed easily and with high accuracy, the first light modulation element unit and the second light modulation element unit may be temporarily changed due to changes over time. Even if the positional relationship between the position and the position is shifted, readjustment of the position can be easily performed.

FIG. 3 is a diagram illustrating a configuration of an optical system of a projector PJ according to an embodiment. The figure which shows typically the positional relationship of the light modulation element by which the position adjustment was carried out by the 1st light modulation element position adjustment process and the 2nd light modulation element position adjustment process. The figure which shows typically the synthetic | combination image light by the polarization | polarized-light synthetic | combination prism when position adjustment is carried out by the light modulation element unit position adjustment process. The functional block diagram of the projector PJ which concerns on embodiment.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a diagram illustrating a configuration of an optical system of a projector PJ according to the embodiment. As shown in FIG. 1, the projector PJ according to the embodiment emits light including first color light (red light), second color light (green light), and third color light (blue light). A light source 100, an integrator optical system 200, a polarization separation mirror 300 as a polarization separation optical system, a first light modulation element unit 400 that emits first image light, and a first polarization component separated by the polarization separation mirror 300 The first light guide optical system 500 that guides the first light modulation element unit 400 (referred to as p-polarized light), the second light modulation element unit 600 that emits the second image light, and the first light separation element 300 separated by the polarization separation mirror 300. A second light guiding optical system 700 that guides two polarized components (referred to as s-polarized light) to the second light modulation element unit 600, a polarization combining prism 800 as a polarization combining optical system, and a polarization combining prism 8 The image light combined by 0 and a projection optical system 900 for projecting an enlarged on the screen SCR.

  The first light modulation element unit 400 includes a light modulation element 410R for red light, a light modulation element 410G for green light, a light modulation element 410B for blue light, and the light modulation elements 410R, 410G, and 410B. And a cross dichroic prism 420 as a first color combining optical system that combines the modulated red light, green light, and blue light. Each of the light modulation elements 410R, 410G, 410B and the cross dichroic prism 420 have an integrated structure and is also called a panel-on prism (POP).

Each of the light modulation elements 410R, 410G, and 410B is disposed on the liquid crystal panels 411R, 411G, and 411B, the incident-side polarizing plate disposed on the incident side of the liquid crystal panels 411R, 411G, and 411B, and the exit side of the liquid crystal panel. And an exit side polarizing plate. In addition, the code | symbol of the incident side polarizing plate and the exit side polarizing plate is abbreviate | omitted.
From the first light modulation element unit 400 configured as described above, first image light having a first polarization component (p-polarized light) is emitted.

  The first light guide optical system 500 reflects the red light (R) out of the p-polarized red light (R), green light (G), and blue light (B) that has passed through the polarization separation mirror 300, thereby generating green light. The dichroic mirror 510 that passes the (G) and blue light (B), and the dichroic mirror that reflects the green light and passes the blue light out of the green light (G) and the blue light (B) that has passed through the dichroic mirror 510. 520, a reflection mirror 530 that reflects the blue light (B) that has passed through the dichroic mirror 520, a lens 540 that is provided on the incident side of the reflection mirror 530, a lens 550 that is provided on the emission side of the reflection mirror 530, and a lens 550 A reflection mirror 560 for guiding blue light passing through the light modulation element 410B and red light reflected by the dichroic mirror 510 to the light modulation element 4 And a reflecting mirror 570 for guiding the 0R.

On the other hand, the second light modulation element unit 600 includes a light modulation element 610R for red light, a light modulation element 610G for green light, a light modulation element 610B for blue light, and each of these light modulation elements 610.
A cross dichroic prism 620 as a second color combining optical system that combines red light, green light, and blue light modulated by R, 610G, and 610B, respectively. As with the first light modulation element unit 400, the light modulation elements 610R, 610G, and 610B and the cross dichroic prism 620 have an integrated structure.

Further, each of the light modulation elements 610R, 610G, and 610B is disposed on the exit side of the liquid crystal panels 611R, 611G, and 611B, the incident side polarizing plate disposed on the incident side of the liquid crystal panels 611R, 611G, and 611B. And an exit side polarizing plate. In addition, the code | symbol of the incident side polarizing plate and the exit side polarizing plate is abbreviate | omitted.
From the second light modulation element unit 600 configured as described above, the second image light having the second polarization component (s-polarized light) is emitted.

  The second light guide optical system 700 reflects red light (R) out of the s-polarized red light (R), green light (G), and blue light (B) that has passed through the polarization separation mirror 300, thereby generating green light. A dichroic mirror 710 that passes (G) and blue light (B), and a dichroic mirror that reflects green light among green light (G) and blue light (B) that has passed through dichroic mirror 710 and passes blue light 720, a reflection mirror 730 that reflects blue light (B) that has passed through the dichroic mirror 720, a lens 740 that is provided on the incident side of the reflection mirror 730, a lens 750 that is provided on the exit side of the reflection mirror 740, and a lens 750 A reflection mirror 760 for guiding blue light passing through the light modulation element 610B and red light reflected by the dichroic mirror 710 to the light modulation element 6 And a reflecting mirror 770 for guiding the 0R. The reflection mirror 770 is also used as the reflection mirror 570 of the first light guide optical system 500.

  The polarization combining prism 800 combines and projects the p-polarized first image light emitted from the first light modulation element unit 400 and the s-polarized second image light emitted from the second light modulation element unit 600. Injected into the optical system 900. Then, the combined image emitted from the polarization combining prism 800 is enlarged by the projection optical system 900 to form a large screen image on the screen SCR.

  By the way, the projector PJ having the two light modulation element units, the first light modulation element unit 400 and the second light modulation element unit 600 as described above, includes each light modulation element of the first light modulation element unit 400 and the second light. Of course, a high-luminance large-screen image can be displayed on the screen SCR by making the corresponding pixels of the light modulation elements of the modulation element unit 600 coincide with each other with high accuracy. By projecting by shifting pixels corresponding to each light modulation element of the unit 400 and each light modulation element of the second light modulation element unit 600 by ½ pixel in the diagonal direction (called diagonal pixel shift), A higher resolution image can be displayed.

  In order to enable such oblique pixel shift projection, the corresponding pixels of each light modulation element of the first light modulation element unit 400 and each light modulation element of the second light modulation element unit 600 are oblique with high accuracy. It is necessary to adjust the position with high accuracy so that the pixel is shifted by 1/2 pixel in the direction.

  In the light modulation element position adjustment method of the projector PJ according to the embodiment, a first light modulation element position adjustment step for adjusting the positions of the three light modulation elements 410R, 410G, and 410B of the first light modulation element unit 400, The second light modulation element position adjustment step for adjusting the positions of the three light modulation elements 610R, 610G, and 610B of the second light modulation element unit 600, and the first light modulation element unit that has completed the first light modulation element position adjustment step. 400 and the light modulation element unit position adjustment step for adjusting the position of the second light modulation element unit 600 after the second light modulation element position adjustment step are sequentially performed.

  The first light modulation element position adjustment step and the second light modulation element position adjustment step are performed using a dedicated position adjustment device (referred to as a light modulation element position adjustment device). The first light modulation element position adjustment step and the second light modulation element position adjustment step are performed as steps before the first light modulation element unit 400 and the second light modulation element unit 600 are incorporated into the projector.

  On the other hand, in the light modulation element unit position adjustment process for adjusting the position of the first light modulation element unit 400 and the second light modulation element unit 600, the first light modulation element unit 400 and the second light modulation element unit 600 are connected to the projector PJ. Is incorporated using the image projection function of the projector PJ.

  A light modulation element position adjustment device (not shown) for performing the first light modulation element position adjustment step and the second light modulation element position adjustment step includes a light source and RGB light from the light source. A light guide optical system (see, for example, the first light guide optical system 500 in FIG. 1), a projection lens, and a pattern image data generator for generating pattern image data for position adjustment. . As the optical system used in such a light modulation element position adjusting device, a higher performance than the optical system used in the projector PJ as a product is used, and in particular, a higher performance is used as the projection lens. It is common that

  Using such a light modulation element position adjusting device, the position of each light modulation element 410R, 410G, 410B of the first light modulation element unit 400 is adjusted, and each RGB light modulation element in the second light modulation element unit 600 is also adjusted. The positions of 610R, 610G, and 610B are adjusted. The position adjustment of the light modulation element is performed as follows.

  First, the light modulation element unit (referred to as the first light modulation element unit 400) to be position-adjusted is installed at a predetermined position between the light guide optical system of the light modulation element position adjustment device and the projection lens. Then, the light source is driven, and the light modulation elements 410R, 410G, and 410B are individually driven by the pattern image data output from the pattern image data generator.

  As a result, color light based on the pattern image data is output from each of the light modulation elements 410R, 410G, and 410B, and each color light is emitted from the cross dichroic prism 420, enlarged by the projection lens, and projected onto the screen. In the process of projecting such a pattern image, the light modulation element 410R and the light modulation element 410B are oblique with respect to the reference light modulation element (in the first light modulation element unit 400, the light modulation element 410G). Position adjustment is performed so that the pixel is shifted by 1/2 pixel in the direction. As described above, such position adjustment can be performed with high accuracy and relatively easily because the projection lens of the light modulation element position adjustment device has high performance. The light modulation element position adjustment in the second light modulation element unit 600 can be similarly performed. Details of the position adjustment will be described later.

  FIG. 2 is a diagram schematically showing the positional relationship of the light modulation elements adjusted in position by the first light modulation element position adjustment step and the second light modulation element position adjustment step. FIG. 2A is a diagram schematically showing the positional relationship between the light modulation elements 410R, 410G, and 410B that have been adjusted in the first light modulation element position adjustment step, and FIG. 2B is the second modulation element position. It is a figure which shows typically the positional relationship of the light modulation element 610R, 610G, 610B in which the position was adjusted in the adjustment step.

The first light modulation element position adjustment step will be described. First, the three color lights of RGB are grouped into two groups. That is, one color light (G) among the three color lights of RGB is set as the first group, and the other two color lights (R, B) are set as the second group. Then, the positions of the two light modulation elements 410R and 410B are adjusted so that the corresponding pixels of the two light modulation elements 410R and 410B corresponding to the two color lights of the second group coincide.

  Subsequently, each pixel of the light modulation elements 410R and 410B corresponding to the two color lights of the second group is 1 / in the oblique direction with respect to each pixel of the light modulation element 410G corresponding to one color light of the first group. Position adjustment of the light modulation elements 410R and 410B corresponding to the two color lights of the second group is performed so that the position is shifted by two pixels. Then, the entire fine adjustment is performed so that the light modulation elements have an optimum positional relationship with each other.

By performing such position adjustment, the pixels of the light modulation elements 410R, 410G, and 410B of the first light modulation element unit 400 have a positional relationship as shown in FIG. In FIG. 2A, in order to show the correspondence of the positions of the pixels in the light modulation elements 410R, 410G, and 410B, the pixels of the light modulation elements 410R, 410G, and 410B are shown overlapped on the same plane. ing. Incidentally, in FIG. 2 (a), the square of squares shown in gray pale are pixels P _G of the light modulation element 410G, square grids shown in gray dark light modulation elements 410R, 410B Each pixel P _R , P _B.

As shown in FIG. 2A, the light modulation element 410R and the light modulation element 410B have a positional relationship such that the corresponding pixels coincide with each other with high accuracy. The modulation element 410R and the light modulation element 410B are set at positions shifted by ½ pixel in an oblique direction with respect to the light modulation element 410G. Incidentally, FIG. 2 pixels shown in (a) P _G and P _R, P _B, only the opening portion of each pixel in the light modulation element (liquid crystal panel) are shown, the periphery of the opening non The opening portion is omitted. This is the same in FIG. 2B and also in FIG. 3 described later.

  As described above, in the first light modulation element unit 400, each pixel of the light modulation element 410G is set as a reference position, and each pixel of the light modulation element 410R and the light modulation element 410B is 1 in the oblique direction with respect to the reference position. The position is adjusted so as to be shifted by two pixels.

  In the first light modulation element position adjustment step described above, first, the positions of the two light modulation elements 410R and 410B are adjusted so that the corresponding pixels of the two light modulation elements 410R and 410B match each other. After that, the position adjustment procedure is such that each pixel of the light modulation elements 410R and 410B is adjusted so as to be shifted by 1/2 pixel in the oblique direction with respect to each pixel of the light modulation element 410G. However, the present invention is not limited to this, and the position of the light modulation elements 410R and 410B may be adjusted individually for each light modulation element 410R and 410B with reference to each pixel of the light modulation element 410G.

  For example, position adjustment is performed such that the light modulation element 410R is shifted by 1/2 pixel in the oblique direction with respect to each pixel of the light modulation element 410G, and then light is applied to each pixel of the light modulation element 410G. Position in which the modulation element 410B is adjusted so that the pixel is shifted by 1/2 pixel in the oblique direction, and the whole is finely adjusted so that the positional relationship as shown in FIG. It may be an adjustment procedure. The same applies to the second light modulation element position adjustment step.

  Next, the second light modulation element position adjustment step will be described. In the second light modulation element position adjustment step, the two color lights (R, B) that are the second group in the first light modulation element position adjustment step are set as the third group in the second light modulation element position adjustment step. In the first light modulation element position adjustment step, the color light (G) that is the first group is set as the fourth group in the second light modulation element position adjustment step.

Then, the position adjustment of the two light modulation elements 610R and 610B is performed so that the corresponding pixels of the two light modulation elements 610R and 610B corresponding to the two color lights of the third group match. Subsequently, each pixel of the light modulation element 610G corresponding to one color light of the fourth group is inclined with respect to each pixel of the two light modulation elements 610R and 610B corresponding to two color lights of the third group. The position of the light modulation element 610G corresponding to one color light of the second group is adjusted so that the position is shifted by 1/2 pixel.

By performing such position adjustment, the light modulation elements 610R, 610G, and 610B in the second light modulation element unit 600 have a positional relationship as shown in FIG. In FIG. 2B as well as in FIG. 2A, each pixel of each light modulation element 610R, 610G, 610B is shown in order to show the correspondence of the position of each pixel of each light modulation element 610R, 610G, 610B. Are superimposed on the same plane. Incidentally, in FIG. 2 (b), the square of squares shown in gray dark colors, light modulation elements 610R, there each pixel P _R, P _B of 610B, square grids shown in gray pale light modulator a pixel _{P G} element 610G.

  As shown in FIG. 2B, the light modulation element 610R and the light modulation element 610B have a positional relationship such that corresponding pixels coincide with each other with high accuracy. Then, the light modulation element 610G is set at a position shifted by ½ pixel in the oblique direction with respect to the light modulation element 610R and the light modulation element 610B having such a positional relationship.

  As described above, in the second light modulation element unit 600, each pixel of the light modulation elements 610R and 610B is set as a reference position, and each pixel of the light modulation element 610G is ½ pixel obliquely with respect to the reference position. The position is adjusted so that the positional relationship is shifted.

  Next, the light modulation element unit position adjustment process will be described. In the light modulation element unit position adjustment step, the position adjustment between the first light modulation element unit 400 that has completed the first light modulation element position adjustment step and the second light modulation element unit 600 that has completed the second light modulation element position adjustment step. Is to do. Further, as described above, the light modulation element unit position adjustment process includes the first light modulation element unit 400 that has completed the first light modulation element position adjustment process and the second light that has completed the second light modulation element position adjustment process. In a state where the modulation element unit 600 is actually incorporated in the projector PJ as a product, the light source 100, the polarization separation mirror 300, the first light guide optical system 500, the second light guide optical system 700, and the polarization composition of the projector PJ. The image projection function such as the prism 800 and the projection optical system 900 is used.

  That is, on the first light modulation element unit 400 side, from a specific light modulation element (one light modulation element corresponding to one color light of the first group) of the light modulation elements 410R, 410G, 410B. The color light is emitted as the first image light, and also on the second light modulation element unit 600 side, a specific light modulation element (two light modulation elements corresponding to two color lights of the third group) among the light modulation elements. ) To emit color light as the second image light.

  Specifically, in the first light modulation element unit 400, by driving a specific light modulation element by the pattern image data, the color light corresponding to the pattern image data is output from the specific light modulation element to the first image light. And the second light modulation element unit 600 side also drives the specific light modulation element by the pattern image data, so that the color light corresponding to the pattern image data is output from the specific light modulation element to the second image. Inject as light.

  The first image light and the second image light are combined by the polarization combining prism 800 and then projected onto the screen SCR by the projection optical system 900. At this time, the positions of the first light modulation element unit 400 and the second light modulation element unit 600 are adjusted so that the image (pattern image) projected on the screen SCR has a predetermined color.

  Here, one light modulation element corresponding to one color light of the first group of the first light modulation element unit 400 is the light modulation element 410G, and two color lights of the third group of the second light modulation element unit 600 are used. The two light modulation elements corresponding to are the light modulation elements 410R and 410B. Accordingly, green light (G) having a p-polarized component is output as first image light from the cross dichroic prism 420 of the first light modulation element unit 400, and from the cross dichroic prism 620 of the second light modulation element unit 600. , S-polarized component red (R) and blue (B) color composite light is output as the second image light. The first image light and the second image light are combined by the polarization combining prism 800, and the combined light is projected onto the screen by the projection optical system 900.

  At this time, the positions of the first light modulation element unit 400 and the second light modulation element unit 600 are adjusted so that the light emitted from the polarization combining prism 800 is white (W). Thus, the positions of the first light modulation element unit 400 and the second light modulation element unit 600 when the light emitted from the polarization combining prism 800 becomes white (W) are the positions of the first light modulation element unit 400. It can be said that this is an ideal positional relationship between the first light modulation element unit 600 and the second light modulation element unit 600. In order to perform such position adjustment, for example, the position of the second light modulation element unit 600 may be adjusted with the first light modulation element unit 400 as a reference. The position of the first light modulation element unit 400 may be adjusted on the basis of the light modulation element unit 600, and the first light modulation element unit 400 and the second light may be adjusted so that they are ideal positions. The positions of both of the modulation element units 600 may be adjusted.

  FIG. 3 is a diagram schematically showing the combined light emitted from the polarization combining prism 800 when the position is adjusted by the light modulation element unit position adjusting step. As shown in FIG. 3, in the first light modulation element unit 400, green light (G) is emitted from the light modulation element 410G as the first image light, and in the second light modulation element unit 600, the light modulation element 410R. , 410B, when the combined light of red light (R) and blue light (B) is emitted as the second image light, if the combined light combined by the polarization combining prism 800 becomes white (W), the first The positional relationship between the light modulation element unit 400 and the second light modulation element unit 600 is an ideal positional relationship.

Incidentally, in FIG. 3 represents the pixels squares of white squares becomes white (W), which includes a pixel P _G of the light modulation element 410G of the first light modulation element unit 400 second light modulator This corresponds to the pixels P _R and P _B of the light modulation elements 610R and 610B in the element unit 600.

  As described above, when the combined light emitted from the polarization combining prism 800 is white (W), the first light modulation element unit 400 and the second light modulation element unit 600 are ideally adjusted in position with high accuracy. It can be said that it is a positional relationship.

  That is, in such an ideal positional relationship, as shown in FIG. 3, the light modulation element 410G in the first light modulation element unit 400 and the light modulation elements 610R and 610B in the second light modulation element unit 600 are: The corresponding pixels are in a matching state, and the light modulation elements 410R and 410B in the first light modulation element unit 400 and the light modulation element 610G in the second light modulation element unit 600 are also in a corresponding state. It becomes. As shown in FIG. 3, each pixel of the light modulation element 410G, the light modulation element 610R, and the light modulation element 610B and each pixel of the light modulation element 410R, the light modulation element 410B, and the light modulation element 610G are respectively The state is shifted by 1/2 pixel in the oblique direction.

As shown in FIG. 3, according to the light modulation element position adjusting method for a projector according to the first embodiment, the same pixel as the oblique pixel shift of the first light modulation element unit and the second light modulation element unit which has been conventionally performed. A shift state can be obtained. That is, the conventional pixel shift of the first light modulation element unit and the second light modulation element unit is performed by changing the corresponding pixels of the RGB light modulation elements 410R, 410G, and 410B in the first light modulation element unit 400. Similarly, in the second light modulation element unit 600, the first light modulation element unit 400 is also adjusted in the second light modulation element unit 600 in a state where the corresponding pixels of the RGB light modulation elements 610R, 610G, and 610B are highly accurately adjusted. These light modulation elements and the corresponding light modulation elements of the second light modulation element unit 600 are installed so that the corresponding pixels are shifted by 1/2 pixel. Even when the position adjustment by the light modulation element position adjustment method of the projector according to the embodiment is performed, as shown in FIG. 3, the same pixel as the oblique pixel shift of the first light modulation element unit and the second light modulation element unit A shift state can be obtained.

  FIG. 4 is a functional block diagram of the projector PJ according to the embodiment. As shown in FIG. 4, the projector PJ includes an image data input unit 11 for inputting an image to be displayed, various user interface information (I / F information) such as user instructions (including position adjustment instructions) and settings. ), An image data storage unit 13 that temporarily stores the input image data and stores pattern image data for position adjustment for performing position adjustment. , A parameter storage unit 14 that stores parameters for performing various correction processes, the light source driving unit 15 that drives the light source 100 (see FIG. 1), and the light modulation elements 410R, 410G in the first light modulation element unit 400, The optical modulation elements 16R, 16G, and 16B that respectively drive 410B (see FIG. 1), and the second optical modulation element unit 600, respectively. Light modulation element driving units 17R, 17G, and 17B for driving the elements 610R, 610G, and 610B (see FIG. 1), image data input to the image data input unit 11, and I input to the I / F information input unit 12, respectively. The image display control unit 18 performs overall control for operating the projector PJ such as processing based on / F information.

  The image display control unit 18 also performs control to drive specific light modulation elements of the first light modulation element unit 400 and the second light modulation element unit 600 when performing the light modulation element unit position adjustment step. For example, when a position adjustment instruction is input from the I / F information input unit 12, the image display control unit 18 sets the projector PJ to the position adjustment mode, and receives pattern image data for position adjustment from the image data storage unit 13. Control is also performed so that the read pattern image data is supplied to a predetermined light modulation element driving unit.

  Specifically, in the position adjustment mode, the image display control unit 18 drives the light modulation element 410G of the first light modulation element unit 400 and drives the light modulation elements 610R and 610B of the second light modulation element unit 600. Control is performed. Then, the pattern image data for position adjustment is read from the image data storage unit 13 and applied to the corresponding light modulation element driving units (in this case, the light modulation element driving units 16G, 17R, and 17B).

  Thereby, in the first light modulation element unit 400, the light modulation element 410G is driven, and in the second light modulation element unit 600, the modulation elements 610R and 610B are driven. Therefore, the green light (G) modulated based on the pattern image data is output as the first image light from the cross dichroic prism 420 (see FIG. 1) of the first light modulation element unit 400, and the second light modulation is performed. From the cross dichroic prism 620 (see FIG. 1) of the element unit 600, the color combined light of the red light (R) and the blue light (B) modulated based on the pattern image data is output as the second image light. The first image light and the second image light are combined by the polarization combining prism 800, and the combined light is projected onto the screen SCR (see FIG. 1) by the projection optical system 900 (see FIG. 1).

As a result, an image based on the position adjustment pattern image data can be projected onto the screen SCR, and the image (position adjustment pattern image) displayed on the screen SCR is white (W). If the positions of the light modulation element unit 400 and the second light modulation element unit 600 are adjusted, the first light modulation element unit 400 and the second light modulation element unit 600 can be set to ideal positions.

  In FIG. 4, the pattern image data for position adjustment is stored in the image data storage unit 13 and read out from the image data storage unit 13, but the present invention is not limited to this. The image data for adjustment may be given to the image data input unit 11 from the outside.

  Note that when the position of the first light modulation element unit 400 and the second light modulation element unit 600 is adjusted so that the image projected on the screen SCR (see FIG. 1) is white (W), the area of the entire image Is preferably as white as possible. That is, due to the influence of the optical system or the like, unevenness may occur in the degree of white in the entire area of the image projected on the screen SCR. In such a case, it is preferable to adjust the positions of the first light modulation element unit 400 and the second light modulation element unit 600 so that the degree of white is as uniform as possible in the entire image.

  Such position adjustment can be performed by the operator visually observing the image projected on the screen SCR. However, the image projected on the screen SCR is not shown in FIG. It is also possible to take an image based on the picked-up image data. In this case, in a region of the entire image projected on the screen SCR, a plurality of discrete positions are set as sampling positions, and an error of the entire pixel value is reduced as much as possible from pixel values obtained at each sampling point. A method of adjusting the position can be exemplified.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the present invention. For example, the following modifications (1) to (6) are possible.

  (1) In the above embodiment, when the light modulation element unit position adjustment step is performed, the first light modulation element unit 400 has a light modulation element (light modulation element 410G) corresponding to one color light of the first group. In the second light modulation element unit 600, the light modulation elements (light modulation elements 610R and 610B) corresponding to the two color lights of the third group are driven. However, the present invention is not limited to this. In the first light modulation element unit 400, the light modulation elements (light modulation elements 410R and 410B) corresponding to the two color lights of the second group are driven, and in the second light modulation element unit 600, the fourth group is driven. Alternatively, the light modulation element (light modulation element 610G) corresponding to one color light may be driven.

  (2) In the above embodiment, when the light modulation element unit position adjusting step is performed, the light modulation element (light modulation element 410G) corresponding to one color light of the first group is driven, and the second light modulation element unit In 600, white (W) is emitted by driving the light modulation elements (light modulation elements 610R and 610B) corresponding to the two color lights of the third group, but the second light modulation element unit 600 Of the two light modulation elements 610R and 610B, only one of the light modulation elements (for example, only the light modulation element 610R) may be driven. In this case, position adjustment is performed based on the color obtained by combining green light (G) and red light (R).

(3) In the above embodiment, when the three color lights corresponding to RGB are grouped into two groups, the green light (G) is made into one group, and the red light (R) and the blue light (B) are combined. The case where grouping is performed so as to form one group has been described as an example. However, the method is not limited to such grouping. For example, green light (G) and blue light (B) are set to 1 The red light (R) may be one group, the green light (G) and the red light (R) may be one group, and the blue light (B) may be one group. You may make it.

  (4) In the above embodiment, the case where the corresponding pixels of the first light modulation element unit 400 and the second light modulation element unit 600 are adjusted so as to be shifted by 1/2 pixel in the oblique direction is exemplified. The shift direction and the pixel shift amount are not limited to this.

  (5) In the above embodiment, the light from one light source is separated into p-polarized light and s-polarized light by the polarization separation optical system (polarization separation mirror 300), and the p-polarized light and s-polarized light respectively correspond to the image forming units. (The first light modulation element unit 400 and the second light modulation element unit 600) are provided, but using two light sources, light from one light source is converted to p-polarized light by a polarization conversion element, and from the other light source. The light may be converted into s-polarized light by the polarization conversion element and supplied to the corresponding light modulation element units (first light modulation element unit 400 and second light modulation element unit 600).

  (6) In the above embodiment, the case where a lamp having an arc tube is used as the light source is exemplified, but a solid light source such as an LED (light emitting diode) can also be used.

  DESCRIPTION OF SYMBOLS 100 ... Light source, 300 ... Polarization separation mirror (polarization separation optical system), 400 ... 1st light modulation element unit, 410R, 410G, 410B ... Light modulation element, 411R, 411G, 411B ... Liquid crystal panel, 420... Cross dichroic prism (first color synthesis optical system), 500... First light guide optical system, 600... Second light modulation element unit, 610 R, 610 G, 610 B. Light modulation element, 611R, 611G, 611B ... liquid crystal panel, 620 ... cross dichroic prism (second color synthesis optical system), 700 ... second light guide optical system, 800 ... polarization synthesis prism ( Polarization synthesis optical system), 900... Projection optical system

Claims (7)

The first image light is emitted by synthesizing the three light modulation elements corresponding to the first color light, the second color light, and the third color light having the first polarization component and the respective color lights respectively modulated by the three light modulation elements. A first light modulation element unit including a first combining optical system, three light modulation elements corresponding to the first color light, the second color light, and the third color light having a second polarization component, and the three light modulation elements A second light modulating element unit including a second combining optical system that emits the second image light by combining the respective color lights respectively modulated by the first light modulating element unit and the first image emitted from the first light modulating element unit A light modulation element position adjustment method for a projector, comprising: a polarization combining optical system that combines light and second image light emitted from the second light modulation element unit to emit combined light;
The three light modulation elements in the first light modulation element unit, with one color light of the first color light, the second color light and the third color light as a first group and the other two color lights as a second group Pixels corresponding to each of the two light modulation elements corresponding to the color light of the second group coincide with each other and for each pixel of the one light modulation element corresponding to one color light of the first group A first light modulation element position adjustment step for adjusting the positions of the pixels of the two light modulation elements corresponding to the two color lights of the second group so as to be shifted by a predetermined amount in a predetermined direction;
In the first light modulation element position adjustment step, the two color lights as the second group are set as a third group, and in the first light modulation element position adjustment step, the one color light set as the first group is set as a fourth group. Among the three light modulation elements in the second light modulation element unit, corresponding pixels of two light modulation elements corresponding to two color lights of the third group coincide with each other, and 2 in the third group. Each pixel of one light modulation element corresponding to one color light of the fourth group is shifted by a predetermined amount in a predetermined direction with respect to each pixel of two light modulation elements corresponding to one color light. A second light modulation element position adjusting step for adjusting the position;
Color light from a specific light modulation element among the three light modulation elements in the first light modulation element unit is emitted as first image light, and the three light modulation elements of the second light modulation element unit A step of emitting colored light as a second image light from a specific light modulation element, and a color of the synthesized light obtained by synthesizing the first image light and the second image light by the polarization synthesis optical system become a predetermined color. Adjusting the position of the first light modulation element unit and the second light modulation element unit.
A light modulation element position adjusting method for a projector, comprising: The light modulation element position adjusting method for a projector according to claim 1,
The first light modulation element position adjustment step and the second light modulation element position adjustment step are performed as steps before incorporating the first light modulation element unit and the second light modulation element unit into the projector,
The light modulation element position adjustment method for a projector, wherein the light modulation element unit position adjustment step is performed in a state where the first light modulation element unit and the second light modulation element unit are incorporated in the projector. In the light modulation element position adjustment method of the projector according to claim 1 or 2,
In the first light modulation element unit, the specific light modulation element is one light modulation element corresponding to one color light of the first group, and in the second light modulation element unit, the third light modulation element is the third light modulation element. A light modulation element position adjusting method for a projector, comprising two light modulation elements corresponding to two color lights of a group. In the light modulation element position adjustment method of the projector according to claim 1 or 2,
In the first light modulation element unit, the specific light modulation element is two light modulation elements corresponding to two color lights of the second group, and in the second light modulation element unit, the fourth light modulation element is the fourth light modulation element. A light modulation element position adjusting method for a projector, wherein the light modulation element is one light modulation element corresponding to one color light of a group. In the light modulation element position adjustment method of the projector according to claim 1,
The light modulation element of a projector, wherein the predetermined direction when performing position adjustment so as to be shifted by a predetermined amount in the predetermined direction is an oblique direction, and the predetermined amount is 1/2 pixel Position adjustment method. In the light modulation element position adjustment method of the projector according to any one of claims 1 to 5,
The first to third color lights are red, green and blue,
One light modulation element corresponding to one color light of the first group in the first light modulation element unit is a light modulation element corresponding to the green light, and 2 corresponding to two color lights of the second group. The two light modulation elements are a light modulation element corresponding to red light and a light modulation element corresponding to blue light,
Two light modulation elements corresponding to the two color lights of the third group in the second light modulation element unit are a light modulation element corresponding to red light and a light modulation element corresponding to blue light, and the fourth group One light modulation element corresponding to one color light is a light modulation element corresponding to the green light.
A method of adjusting a position of a light modulation element of a projector. The first image light is emitted by synthesizing the three light modulation elements corresponding to the first color light, the second color light, and the third color light having the first polarization component and the respective color lights respectively modulated by the three light modulation elements. A first light modulation element unit including a first combining optical system, three light modulation elements corresponding to the first color light, the second color light, and the third color light having a second polarization component, and the three light modulation elements A second light modulating element unit including a second combining optical system that emits the second image light by combining the respective color lights respectively modulated by the first light modulating element unit and the first image emitted from the first light modulating element unit A projector comprising: a polarization combining optical system configured to combine light and second image light emitted from the second light modulation element unit to emit combined light;
The position of the three light modulation elements of the first light modulation element unit is adjusted by the first light modulation element position adjustment step in the light modulation element position adjustment method for a projector according to any one of claims 1 to 6. And
The position of the three light modulation elements of the second light modulation element unit is adjusted by the second light modulation element position adjustment step in the light modulation element position adjustment method for a projector according to any one of claims 1 to 6. And
The position of the first light modulation element unit and the second light modulation element unit is adjusted by the light modulation element unit position adjustment step in the light modulation element position adjustment method for a projector according to any one of claims 1 to 6. A projector characterized by having